1. Field of the Invention
This invention relates to a dial gauge case, which can be utilized for a usual dial gauge for magnifying a stroke or displacement of a spindle with a magnifying mechanism such as a rack-and-pinion assembly.
2. Description of the Prior Art
A usual dial gauge magnifies a stroke or displacement of a spindle having a probe or measuring pin provided at an end with a pinion-and-rack assembly or like magnifying mechanism, and displays the magnified stroke or displacement as a corresponding rotation of a pointer.
Such a dial gauge permits even a very small displacement of the probe to be confirmed as a great rotation of the pointer, thus permitting high accuracy measurement.
FIGS. 10 and 11 show a well-known dial gauge 10.
The illustrated dial gauge 10 comprises a dial gauge case 40, which accommodates a dial gauge mechanism including a scale board 20 and a pointer 30, and a spindle 50 penetrating a peripheral wall 41 of the case 40.
A cylindrical stem 60 projects outward from the peripheral wall 41, and accommodates the spindle 50.
The stem 60 protects the spindle 50, and serves a mounting portion to be mounted in a support which supports the dial gauge 10.
The inside of the dial gauge case 40 is as shown in FIG. 12. In the case 40 and the stem 60, bearings 42 and 64 are provided such that they face each other in the direction of sliding of the spindle 50, thus permitting smooth sliding of the spindle 50.
In the above usual dial gauge 10, the case 40 is fabricated as a one-piece casting of zinc, and the bearings 42 and 64 are fabricated by using bronze or like material having satisfactory frictional properties.
In the assembling of the dial gauge 10, therefore, it is necessary to mount the bearings 42 and 64 in the peripheral wall 41 and the stem 60, respectively, giving rise to the problem that the efficiency of dial gauge manufacture is reduced with increased number of parts and increased number of assembling steps.
It is conceivable to fabricate the case 40 and bearings 42 and 64 altogether as a one-piece molding of bronze. Doing so, however, results in an extreme increase of the material cost of the case 40.
The invention seeks to solve the above problems, and it has an object of providing a dial gauge case, which permits reducing the number of dial gauge components and improving the efficiency of dial gauge manufacture without greatly increasing the material cost of the dial gauge.